Friday 20 August 2004 21.56 EDT
First published on Friday 20 August 2004 21.56 EDT

White Gold: The Extraordinary Story of Thomas Pellow and North Africa's One Million European Slaves by Giles Milton 352pp, Hodder, £18.99

It is commonly accepted that more than 15 million Africans were brutally enslaved in the 17th and 18th centuries, the majority of them captured in west Africa by Arab traders. In White Gold, Giles Milton illuminates the less-well-known history of the Europeans who were captured for the north African slave markets by Barbary pirates. He asserts that there may have been one million such "white slaves" seized from Spain, France, England and even the fledgling American colonies.

The "Extraordinary Story of Thomas Pellow" is a lens through which the wider story of the relationship between the emerging European maritime powers and the long-established sultanates of Barbary is told. Two remarkable characters form the linchpins of this story: Pellow, a Cornish boy, and Sultan Moulay Ismail, the ruler to whom he was enslaved.

The 11-year-old Pellow was unfortunate enough to be taken prisoner along with the rest of the five-man crew of the Francis in the summer of 1715. They had set sail from Cornwall en route to Genoa with a cargo of salted pilchards. The voyage was the beginning of 23 years' imprisonment at the hands of a savage despot. Taken to the enormous Moroccan imperial palace at Meknes, Pellow's first sight of the sultan was on a gilded chariot being drawn by a harnessed band of wives and eunuchs. Sultan Moulay Ismail appears almost like a pantomime emir, "wrapped in fabulous silks and damasks, with a voluminous silk turban, his waist-length cloak wrought all over with silver and gold and bright red riding boots..."

Milton reveals a man whose "common diversion was, at one motion, to mount his horse, draw his scimitar and cut off the head of the slave who holds his stirrup". Displeased at news that some of his concubines had been visiting one another without permission, he punished more than a dozen of them by extracting all of their teeth. Unsurprisingly, Pellow had a miserable time as a young slave. After months of torture, which included the infamous bastinado (being suspended by the ankles and beaten on the soles of the feet), he converted to Islam. While Pellow later wrote that his conversion was made purely under duress, and that God would forgive him, "knowing that I never gave up the consent of the heart", his conversion had serious practical consequences. First, it meant he would suffer a brutal circumcision, and more seriously he would not be eligible for ransom, since apostates gave up their right to Christian salvation.

Pellow's strength of character and quick mind impressed the sultan. He ordered that Pellow be instructed in Arabic and put to work as a palace retainer. He was eventually made a guard in the royal household on the fringes of the royal harem. He was on duty one night when the sultan banged on the outer door demanding to be let into the harem. According to protocol he was supposed to send advance warning of a conjugal visit. The boy (now 15) shouted through the door telling Ismail that "he must be an impostor" since the real sultan was so honourable that he would never break palace protocol in such a way. Pellow then fired a warning shot to frighten the "impostor" away, and listened while the sultan described the revenge he would take in the morning.

Yet the sultan recognised Pellow's loyalty and he rose further within the household, eventually becoming a personal attendant and carrying a wooden club with which Ismail would frequently "knock his people on the head".

Further adventures included being sent to command a remote garrison fort, being assigned a Muslim wife with whom he had a child, and two failed attempts at escape. The deaths of Pellow's wife and daughter perhaps provided him with the final incentive and, after a slave-capturing expedition across the Sahara, he eventually found passage on a ship to the British colony at Gibraltar. He reached London in 1738. In an Odysseus-like homecoming to Penryn, he was amazed to find his parents still alive. He eventually went on to write a best-selling account of his travels - a document on which Milton understandably draws heavily.

It is not just Pellow's extraordinary life that holds the attention in White Gold. Behind Moulay Ismail's despotic personality Milton detects "vainglorious dreams of restoring Morocco to a position in which the country would be considered the equal of the great powers in Europe". Capturing large numbers of white slaves was part of a strategy to gain leverage over "the great powers of Christendom". English females, it seems, were sometimes ransomed for more than £1,000.

We can only be awed by the financial power that allowed Ismail to order giant platters that could hold enough couscous to feed 900 people or to command the laying of foundations for 50 adjoining palaces at Dar al Makhzen with stables for 12,000 horses. And behind it all lay what Milton calls a fanatical religious devotion "that was provoking a growing backlash against Islam in almost every nation in Europe".

When Moulay Ismail sent a Moroccan ambassador to the court of Charles II, the diarist John Evelyn reported that the delegation "drank a little milk and water... and they did not looke about or stare on ye ladies...". However, on their return to Morocco Ismail accused the ambassador and his men of being too friendly with their Christian hosts. The ambassador was put in chains and his companions castrated. Gripping though such details are, it is in Milton's almost casual asides that the repetitive and painful echoes of history are most keenly felt. In dealing with the plight of hapless slaves taken from New England, for example, he tells us that "Few in colonial North America were interested in understanding the world of Islam, and even in Britain there was almost no desire to peer beneath the surface of the frightening world of Barbary".

If there is a fault in this book it lies perhaps in Milton's brief attempts to infiltrate himself into the narrative. These interludes are rather tentative compared to his confident recounting and reconstruction of 18th-century Moroccan life. But Milton has ingeniously retrieved and polished a hidden nugget from the remarkable treasure house of British history.

· Tim Ecott's latest book, Vanilla: Travels in search of the Luscious Substance, is published by Michael Joseph.